[olddog]

Let's back up a bit and make sure the accused is guilty.

Two coils failing is quite unlikely. Two coils and now two TFI, makes me think the problem is elsewhere. How are you determining that there is no spark? Where are you checking if there is no spark (at coil or at the plug)? Even if there is no spark at the plug, the coil could be working perfectly and it is lost in a wire, rotor, or cap. You get my point.

If you are basing this on the engine does not run, no fuel or too much fuel will kill an engine, same as no spark. ECU, MAF, TPI, or a loose ground can all cause this. Believe me, I replace everything in the ignition system and the ECU, before I realized it was a fuel problem.

The TFI modules have a bad reputation, and they do fail if they are in too much heat. Ford later moved them to a heat sink on the fender well. You can find instruction on moving the TFI with a google search. I moved mine and is stays cool to touch, where it used to get too hot to touch on the distributor.

The Ford part are excellent stuff. You should not be having all the problems that you are. Are you certain the parts you have replaced were indeed bad?